The goal of this grant is to gain sufficient training and experience to optimally use cognitive neuroscience methods to advance the study of autism spectrum disorders (ASDs) and their symptoms. Autism involves impairments in social behavior, communication, and restricted and repetitive behaviors or interests. Autism can be characterized as a disorder in which individuals become fixated on thoughts and/or behaviors. Cognitive control refers to the ability to flexibly allocate mental resources to guide thoughts and actions in light of internal goals. It involves the ability to represent and maintain behaviorally-relevant information, or "context," to support adaptive responding. The central tenet of this application is that individuals with ASDs have an impairment in the brain systems underlying cognitive control. Regions of the brain that have been closely associated with cognitive control include the dorsolateral prefrontal cortex (DLPFC), the anterior cingulate cortex (ACC), and the parietal cortex (PPC). In the proposed studies, I will use well-established cognitive neuroscience probes to investigate the functional status of cognitive control systems in individuals with ASDs. I will particularly address impairments in these systems and their relationship to the severity of restricted and repetitive behaviors. Aim 1 uses two behavioral experiments to investigate forms of cognitive control including overcoming a prepotent response tendency and task switching in individuals with ASDs aged 12 to 18. Aim 2 uses event-related functional neuroimaging (fMRI) to examine the role of the prefrontal cortex (RFC), anterior cingulate cortex (ACC), and parietal cortex in cognitive control in individuals with ASDs compared to typically developing control subjects. Aim 3 relates behavioral and neuroimaging findings to measures of the restricted and repetitive behavior symptoms. Consistent with the objectives of the National Institutes of Health Intragency Autism Coordinating Committee (IACC) Research matrix, improved integration of the fields of clinical neuropsychology and cognitive neuroscience holds the potential to advance our understanding of clinical symptoms, to illuminate distinctions between autism and related developmental problems, and to inform the development of treatments. The training and research plans outlined in this application will prepare the Candidate to participate as a senior investigator in efforts to achieve these goals.